bike won't run

[Medi]

My friend tried to turn it on the other day after a 3 hour ride to bring it home - no go... and I just got it

Bike sat for two days and seems to turn over but doesn't start. When I bough it we turned it on and off a few times with no problems whatsoever. Owner gave me a list of things that were done to it about 2 months ago which included cleaned and rebuilt carbs, replaced petcock o-ring and seals.

I'm going away for the July 4th weekend so I won't get to look at it until the weekend after. I know it's not a lot of information but if anyone has an idea what it might be.

Thanks

[andyb]

If the carbs were cleaned two months ago and it sat, that means absolutely nothing.  Fuel can easily go bad and start gumming stuff up in that timeframe if it's not stored well.


Past that, you probably should give a little more information.  Like, does it turn over, does it not idle, etc.  "Not start" is pretty vague.

[racerman_27410]

are you using the choke ?



Kookaloo!

[Medi]

It does turn over and my friend first tried it without choke and than with choke. The bike was ridden home (3 hour ride) and than sat two days in the garage. Another thing i remembered was the fuel was low when we got the bike so we stopped by a gas station and filled it up full with premium fuel. I'll try to get more information today or tomorrow.

[RichBaker]

Bad fuel?  I've seen some bad premium around here lately, people aren't using it and it sits in the tank too long. Or, water in the fuel...

[Medi]

ok, so my friend is saying the bike is turning over and almost starting but it doesn't.. I'm going over his place on Friday and try to get some good fuel into the bike.

Thanks

[racerman_27410]

check to make sure the choke is actually opening the choke circuit instead of just the cable moving .

you can see it really well once the seat and right hand sidepanel are off the bike.



KOokaloo!

[chapindad]

Is it turning over strongly or weakly?  Could be a battery starting to go.

[Pat Conlon]

After you inspect and verify that the choke rod is actually moving, per Racerman's above suggestion, then you have a Clogged choke circuit:

Here's what our esteemed Carb Guru, DavidR  has to say:

If you're having trouble getting the motor started when cold and using the choke,
then the choke fuel circuit may be clogged.

Here's what you need to inspect.

Take off the float bowls and you will see a small hole on the side of the bowl
near the botton.  This hole is connected to a cast-in tube that runs up the side
of the bowl and lines up with a brass tube on the carb body.  This tube is the
source for fuel for the choke circuit.  It is trying to pull fuel from the float
bowl.  There is a tiny orifice in that float bowl port that is probably clogged.

When this happens, the choke essentially quits working and can make starting
worse because when it doesn't deliver any fuel to the intake, it lets in even
more air to an already lean mixture maing starting very hard.

Make sure these orifices are not clogged!

DavidR.

[Medi]

We were finally able to start it after some battery charging and choking than some more battery charging, all in all about 3 - 4 times. At the last attempt it took about 2 minutes of engine turning over very strongly like it's almost running and than it ran! After about 2 - 3 minutes it shut off by itself and started right back up like a brand new bike. We turned it on and off multiple times after that and it did it with no problems.
After that I finally took it for a first ride which was a bit scary - not being used to the position. After I got it home I filled it up with a premium and added carb cleaner.
Today she didn't start again
Same problem as before, engine turns over but doesn't start with and without choke. We took some video of trying to start it, I will post it tonight after I get it converted.

So far I noticed that it stops running after filling up with gas, we did look into the tank to see that there is some rust on the side walls and much less on the bottom.
I will also check for choke rod and clogged choke circuit either today or tomorrow.

[jack02]

So far I noticed that it stops running after filling up with gas, we did look into the tank to see that there is some rust on the side walls and much less on the bottom.I will also check for choke rod and clogged choke circuit either today or tomorrow.

Me too... but I caught it before it stopped the bike from running,got as far as a stumble off idle and occasional coughing and spluttering quite randomly. I've already stripped,cleaned and refitted the carbs,but tbh there was no sign of contamination whatsoever away from the bottom of the float bowls. I've got me a bag of aquarium gravel and that's gonna get shoved in the tank and shaken around tomorrow to hopefully abrade away the rust. Anyone know of a better way,and if I need to treat the tank further?

[Arnie]

I'd use a fist full of 1/4" nuts instead of the gravel.  At least you'll be able to get them all out again with a magnet.  I'd also put a cup of "rust converter" into the tank with the nuts before all your shaking.

Cheers,
Arnie

[jack02]

I'd use a fist full of 1/4" nuts instead of the gravel.  At least you'll be able to get them all out again with a magnet.  I'd also put a cup of "rust converter" into the tank with the nuts before all your shaking.

Cheers,
Arnie

Crap,I'd already gone and poured the gravel in before reading this! It appears to have scrubbed most of the rust out - tho' gawd knows what's lurking still in the recesses of the tank. Getting the gravel out/drying the tank was a right hassle. I did it by getting an old,thin blanket and feeding the lot in thru' the filler hole,then rolling the tank around so the blanket absorbed all the 'loose' water. Then used the missus' hairdryer to blow into and around the outside of the tank to hasten evaporation. This worked better than I'd any right to expect. Tank now dry but still retaining huge amounts of gravel,so I stood it upright and rapped the sides and base to make all the crap stuck to the sides fall to the bottom (the bit where the fuel gauge sender goes). Then I got the vacuum cleaner and taped about 18" of 10mm ID plastic tubing to the nozzle so's I could suck out all the junk from the bottom,via the aforementioned hole. The noise of just one bit of gravel bouncing around in the tank is very obvious. Repeated the rapping of the tank and sucking out the bits until no more noise was forthcoming. Will go get some rust converter to care for the bits inevitably missed,when time allows. Hopefully job done. BTW Arnie,I did employ your recent tip of removing the subframe bolts to ease the pain of carb removal and refitting - the whole odious job was certainly not as fraught as I'm used to!

[Arnie]

It takes YEARS (or decades) of painfully bad technique to get "experience".   
Or, maybe just waiting a day or two before diving in to a job to allow those who have already "been there, done that" to reply with a less difficult method to accomplish the same thing.

Arnie

[carsick]

Hell I'm always late so now that you've done the gravel-
BB's (for an air rifle AKA BB gun) work pretty good for this and the magnet gets 'em out too. Also I just used the POR-15 kit on a tank that sat with some gas in it for 21 YEARS!! It was time consuming but the results are incredible. Caustic solution to strip the gum, acid to strip the rust, rinse & blow dry, pour in the super paint, roll around and drain to prevent puddles, dry for four days and good for a long, long time.